Field of the Invention
This invention relates to the field of alarms that make possible the surveillance of secure spaces located in buildings or structures, and has as its object a method for detecting, recognizing, and automatic disarming of an alarm control unit and an alarm system suitable for using said method.
Description of the Related Art
Alarm systems are already known that comprise an alarm control unit powered by an autonomous energy source or by the electric network and connected by wire or wirelessly (radio frequency) to at least one badge reader located in the area of a door. The reader generally has a keypad to enable the entering of a personal identification code intended to be authenticated by the control unit by being compared to a list of authorized identification codes stored in the latter.
When the code is recognized by the alarm control unit, the system controls the procedure for disarming the alarm control unit that consists in performing several operations such as, for example: indicating to certain elements of the system the change in status, modifying the signaling of the indicator lights that go, for example, from red to green, displaying a message on the screen of the keypad, communicating with a remote monitoring center, or else recording the event in the system log. When the identification code is not recognized by the control unit, it then generates an alarm procedure that generally consists in triggering a sound alarm and/or an alarm in the form of a response procedure directly at the secure site or remotely.
Such systems generally comprise a manual arming means such as a key or a code that enables the user to arm the control unit when he leaves the secure space.
Other alarm systems are also known that avoid the user entering a code using the button keypad of the reader, by inserting or by sliding an individual badge, which contains in its memory an identification code, into a slot that is specially provided in the reader or by presenting a contactless badge or transponder badge in the vicinity of the reader.
The contactless badge reader is commonly called a proximity reader and is designed to communicate, using a proximity transmitter/receiver, with the transponder badge by radiofrequency and to transmit an interrogation signal in the direction of said transponder badge, located in its communication field, i.e., its emission field, at a suitable distance. The transponder badge, after having received the interrogation signal coming from the reader, is designed to be able to transmit in return an identification signal destined for the proximity reader by using the energy contained in the interrogation signal.
Subsequently, the proximity reader, using a communication module, transmits the identification signal to the alarm control unit that generates an alarm procedure, such as the one described previously, if the identification signal is not authenticated and validated by the control unit.
Such technology for remotely reading a transponder badge is well known under the name of RFID technology, an abbreviation for the English term “Radio Frequency Identification.” This type of badge is of the “passive” type, i.e., it does not comprise a power source.
However, this technology requires significant power to obtain an effective covering zone for the proximity reader. Actually, the proximity reader must be permanently or periodically activated to be in service when a transponder badge is near, in its transmit field, with a more or less short reaction time, depending on the application. The proximity reader must therefore be connected to a power source that is permanent and consistent, particularly of the public power grid type.
In addition, the power consumption of the proximity reader is not restricted to its exchanges with transponder badges but can also result from various communications between said proximity reader and the alarm control unit.
The electric power consumption of the proximity reader is therefore a crucial problem when it must be rendered autonomous, with its own power source, this in order to avoid any electrical wiring of the proximity reader, particularly with an external power supply of the public power grid type, and to make possible an easy installation of said proximity reader at strategic locations, particularly in the area of a door for access to a secure space that is alarmed and/or under anti-intrusion monitoring or in the immediate vicinity of the latter by means of an alarm control unit.
To eliminate this problem, the document EP2287812 describes a device for detecting entry into a secure space of a dwelling and for recognizing transponder badges intended to work with an alarm control unit and/or an anti-intrusion monitoring system. The device comprises a proximity reader that is capable of communicating with the transponder badges and that is located in the secure space in the immediate vicinity of the access opening. The reader further incorporates an autonomous electric power supply source, and the device further comprises an assembly of means for detecting entry or passage through the access opening and means that are able, during an entry detection, to automatically control the activation of said proximity reader and the putting of the latter in communication with the control unit and with the transponder badge present, this for the purpose of establishing a transfer of data within the context of a procedure for identifying and recognizing the transponder badge in question, and then, if no authorized badge is recognized and so that an entry detection is effective, within the context of an alarm and/or response procedure by said control unit.
However, if the device of the document EP2287812 provides a standby for the remote identification reader that saves energy intended to activate it when no entry or door opening has been detected, once the system has been disarmed by a person who is identified and authorized to enter, the reader, in the disarmed mode of the control unit, continues to be activated by each detection of a new entry or door opening. Thus, for example in the case of a garage in a house whose door is protected by such a system, the opening of the door several times a day, when the system is disarmed, causes the reader, which is autonomous, to activate as many times, following each detection of opening of the door by the detector, and therefore a power consumption by the reader that is too high does not enable an autonomous operation of long duration.